This invention relates to orthopedic surgery and to an ultrasonic apparatus and process for minimal invasion of skeletal bones in the body for treatment and support.
The use of cannulas to gain access to the interior regions of a patient""s body is very old. In recent history, the use of the cannula in all types of surgery has gained wide acceptance. Heart catheterization and delivery of stints contributed to the increased popularity, as well as laproscopic surgery of all kinds. These techniques have reduced patient trauma, incidence of infection and hospital stays. These procedures have in common gaining access to the interior of the body by a small stab wound through which is inserted a cannula for maintaining a passageway. All sorts of other surgical implements may then traverse this passageway depending on the specific procedure to be performed on the patient.
Vertebroplasty was recently introduced to the medical arts as a percutaneous technique for repairing spinal compression fractures by injecting bone cement into the vertebral body. However, the technique quickly expanded to osteoporotic individuals that had been treated with narcotics and immobilization. The bone cement is used to shore up the collapsing vertebrae for support which relieves the pain associated with undue pressure on the nerves. This procedure rapidly gained acceptance as a substitute for open spinal surgery and vertebral microsurgery.
Radiologists and surgeons are involved in the procedure since the process is monitored by fluoroscopy and has the potential for leakage of the cement into the local blood stream. Some of the critical parameters of the procedure involve the mixing of the cement to an appropriate viscosity, ensuring that the cement is radio-dense for viewing, properly placing the injector inside the cancellous portion of a vertebra, and rigorously controlling injection pressure and quantity. See xe2x80x9cVertebroplasty: Dangerous Learning Curve,xe2x80x9d START-UP, June 2001.
U.S. Pat. No. 6,273,916 to Murphy describes vertebroplasty, generally, as performed on a prepped and draped prone patient who has been injected with a local anaesthetic. A skin incision is made over the selected vertebrae and a needle is inserted in a posterior approach to engage the vertebral body. A suitable cement is prepared using a contrast medium, such as barium powder, mixed with methylmethacrylate powder, and a monomer liquid. The cement (PMMA) becomes unworkable within 4 to 11 minutes from mixing.
Cement is injected into the vertebrae, while visualized by lateral and anterior-posterior X-ray projection fluoroscopy imaging. The injection is halted if the cement starts to extend into unwanted locations, such as the disc space or towards the posterior quarter of the vertebral body where the risk of epidural venous filling and spinal cord compression is greatest. If no unwanted migration is detected, the injection continues until the vertebrae is adequately filled. The amount of cement injected may vary considerably, e.g. from 4 to 36 cc.
Reiley et al, U.S. Pat. No. 6,048,346, teach a posterior-lateral approach for accessing the interior of the vertebrae for injecting bone cement or treatment substances or a combination of both. The bone cement is injected using a caulking gun-like device with a ram rod in the barrel.
In this procedure, the cement follows the cracks and crevices pre-existing in the vertebrae which may result in weak structural areas with little or no cement support between bony outcrops and/or migration of the cement outside the desired boundary through larger fissures before other areas are adequately filled.
Scribner et al, U.S. Pat. No. 6,241,734, teach the use of a balloon inflated within the intra-vertebral space to create a regular shaped void for application of a well shaped charge of cement with greater supporting characteristics. There are attendant risks of rupture of the inflated balloon while it is within the vertebrae. Scribner et al also teach the use of multiple components for gaining access to the intra-vertebral space.
Wuchinich, U.S. Pat. No. 5,167,619 discloses an ultrasonic handpiece used for reaming cement from a long bone preparatory to replacement of a prosthesis. Wuchinich recognizes that incidental contact between the ultrasonic probe and the interior of the bone surface is not injurious to the bone.
The use of an ultrasonic probe in the intervertebral disk is shown by Marcove et al, U.S. Pat. No. 5,976,105. The probe is not inserted within the vertebra body but is applied to the exterior tissues. The Marcove ultrasonic tip is vibrated longitudinally in the frequency range of 25 Khz to 60 Khz which is considered sufficient to soften body tissue. The energy is transmitted to the tip from a handpiece having an ultrasonic transducer connected to a wire extending through a cannula.
The use of an ultrasonic probe for treatment of blood clots is disclosed by U.S. Pat. No. 5,725,494 to Brisken. The vascular probe must be extremely flexible to follow the twists and turns of the blood vessels through which it traverses. The ultrasonic transducer is located at the leading end of the flexible probe.
What is needed in the art is a simple apparatus having several components operated by the same handle to perform cannulazation of skeletal bone including the formation, by ultrasound, of a defined intra-bone cavity for treatment deposits
Accordingly, it is an objective of this invention to teach a percutaneous system for surgery using ultrasonic vibration to shape or destroy tissue.
Also, it is an objective of the instant invention to teach a kit having a guide needle, cannulas, ultrasonic probe, several different cannula tips, a plunger, a clearing tool, a connector and a universal handle.
It is another objective of the instant invention to teach the formation of a cavity within bone or soft tissue, by ultrasonic energy, as well as, modulating and directing the ultrasonic energy to shape the cavity and to visualize the cavity.
It is yet another objective to teach a kit with several interchangeable tips to be fitted on the leading end of the cannula for different penetrations of the body.
It is a still further objective of the invention to teach a kit for orthopedic use to perform bone biopsy and to deliver a biological material to the cancellous portion of bone.
It is a further objective of the invention to teach manipulation of a biological material within the bone to change position, as well as, physical form
It is yet another objective to teach a kit in which the universal tool has plural elements spring biased together and forms a temporary connection with the other components of the kit by operation of the spring bias.
Other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.